chore: remove unreferenced skill files, fix broken GEMINI.md import

[stbenjam]

Who is submitting this PR? (required)

Field	Value
Your model + version	Claude Opus 4.6
Harness + version	Claude Code 2.1.199
All plugins installed	superpowers
Human partner who reviewed this diff	@stbenjam

What problem are you trying to solve?

While running skillsaw lint, it flagged 7 files that are never referenced from their respective SKILL.md (directly or transitively). I investigated each one and confirmed they are genuinely orphaned — leftover from earlier skill development or refactors that replaced subagent dispatch with inline self-review.

Separately, GEMINI.md imports references/gemini-tools.md, which doesn't exist.

Happy to restore or re-reference any of these files if the findings aren't valid.

What does this PR change?

Removes 6 unreferenced files from 3 skills and fixes a broken import in GEMINI.md. Pure deletion, no behavior change.

File	Status	Explanation
skills/systematic-debugging/CREATION-LOG.md	Left in place	Also flagged, but it documents the design rationale behind the skill's deliberate choices — gray area, worth keeping
skills/systematic-debugging/test-academic.md	Removed	Dev-time test prompt, zero references anywhere
skills/systematic-debugging/test-pressure-1.md	Removed	Dev-time test prompt, zero references anywhere
skills/systematic-debugging/test-pressure-2.md	Removed	Dev-time test prompt, zero references anywhere
skills/systematic-debugging/test-pressure-3.md	Removed	Dev-time test prompt, zero references anywhere
skills/brainstorming/spec-document-reviewer-prompt.md	Removed	Orphaned subagent reviewer prompt; brainstorming switched to inline self-review (step 7)
skills/writing-plans/plan-document-reviewer-prompt.md	Removed	Orphaned subagent reviewer prompt; writing-plans switched to inline self-review
GEMINI.md	Fixed	Removed import of nonexistent references/gemini-tools.md

Is this change appropriate for the core library?

Yes — this is housekeeping on existing core skill directories. No new functionality, no third-party dependencies.

What alternatives did you consider?

Could re-reference these files from their SKILL.md instead of deleting, but they serve no runtime purpose — the test prompts were one-time dev artifacts and the reviewer prompts were superseded by inline self-review.

Does this PR contain multiple unrelated changes?

The changes are related: all are dead/broken file references. The GEMINI.md fix is the same category (referencing a nonexistent file).

Existing PRs

• I have reviewed all open AND closed PRs for duplicates or prior art
• Related PRs: none found addressing these specific files

Environment tested

Harness (e.g. Claude Code, Cursor)	Harness version	Model	Model version/ID
Claude Code	2.1.199	Claude Opus 4.6	claude-opus-4-6

Evaluation

• Ran uvx skillsaw lint --rule instruction-imports-valid --rule agentskill-unreferenced-files before and after. 7 warnings → 1 warning (CREATION-LOG.md, intentionally kept, can be allowlisted if repo onboarded to skillsaw).
• No skill behavior changes — only unreferenced files were removed.

Rigor

• This change was tested adversarially, not just on the happy path
• Verified each file is genuinely unreferenced via grep across the repo
• Confirmed the two reviewer prompts were orphaned by refactors (SKILL.md now uses inline self-review)

Human review

• A human has reviewed the COMPLETE proposed diff before submission

[rasibintang]

Supporting evidence for removing the two document-reviewer prompts: they became orphans in e6221a4 ("Replace subagent review loops with lightweight inline self-review"), which deliberately removed their dispatch steps from both SKILL.md files with regression data in the commit message (5 versions x 5 trials: ~25 min overhead, no measurable quality gain) — the prompt files just weren't deleted with it, and the system's test was removed separately in ea8aad8. Full write-up: #1962 (comment). This PR would also resolve #1962 and #1511.